Conventional actuators, such as electromagnetic motors and piezoelectric actuators, are components of many devices including medical instruments, robotic probes, consumer electronics and surveillance systems. Electromagnetic motors and piezoelectric actuators can be expensive and bulky, and can require complicated control electronics.
Shape memory alloy actuators are known, but can involve significant amounts of heat generation and can have high power requirements.
Alternatives to conventional actuators are needed in applications where space and weight are limited, such as laparoscopic medical probes, small robotic probes, and micro-lens positioning systems.
Laparoscopic procedures present a fast growing market in medical robotics. Laparoscopic probes require very small, yet powerful actuators to operate inside a patient's body. Conventional electric motors present limitations in size, weight, and transmission mechanisms.
Lenses placed in cameras, including auto focus and zoom lenses in digital cameras, often use piezoelectric motors, which are expensive to fabricate.
Furthermore, using conventional actuators for orienting small cameras, such as those used in surveillance systems, in small robots, or in consumer electronics, is difficult because conventional actuators typically require transmission mechanisms which add weight and size.